Expansion joint for sectional paving



May 6, 1941.

w. w. KINZER EXPANSION JOINT FOR SECTIONAL PAVING Filed Jan. 30, 1939 Patented May 6, 1941 l JNiTlElD STATES PATENT OFF!CE EXPANSION JOINT FOR. SECTIONAL PAVING William WLKinzer, Lancaster, Pa, assignor to Armstrong Cork Company, Lancaster, Pa., a corporation of Pennsylvania Application January 30, 1939, Serial No. 253,515

' 8Claims. (0!.94-18) This invention relates to expansion joints for sectional concrete paving and similar structures and to the method of making the same. More particularly, this invention relates to preformed expansion joints for such structures which per mit free expansion and contraction of adjacent sections of paving without permitting openings to exist in the structure for the entrance of water or other deleterious matter and to the method of constructing such structures.

This invention has for its chief object to provide a preformed expansion joint of resilient compressible material which yields to absorb stresses of expansion and which expands to seal the space between adjacent sections occasioned by contraction thereof. An object of my invention is to provide a preformed expansion joint of resilient compressible material which will not deteriorate and lose its resilient compressible characteristics'upon exposure to weather or severe trafiic conditions and which may be easily, economically and quickly assembled. Afurther object is to provide a sectional concrete structure in which the sections are free to expand and contract in accordance with weather conditions withcasing enclosing the same, the walls of the cas-= ing compressing the filler to less than its original thickness and being locked in fixed position to maintain the filler in compressed condition therein.

The invention further relates to a method of making such expansion joints in which a resilient filler is formed having a predetermined original thickness and is positioned within a casing, the walls of the casing being forced toward one another to compress the filler to less than its origi- 1 nal thickness, and being then locked in fixed position to retain the filler in compressed form. It will be understoodwhen the joint is placed in a paving structure such casing is unlocked to release the filler and to permit it to expand and recover as much of its original thickness as is permitted by adjacent concrete sections.

The accompanying drawing illustrates a preferred embodiment of my invention in which- Figure l is an isometric View illustrating the expansion joint prior to compression of the filler;

Figure 2 is a sectional view of the expansion joint of Figure 1 in which the filler is held in compressed form;

Figure 3 is a'fragmentary sectional view of a sectional concre e paving structure embodying my invention;

Figure 4 is a sectional view of a modified form of expansion joint illustrating the filler in uncompressed condition; and

Figure 5 is a sectional View of the joint shown in Figure 4, in which the filler is compressed and held in such condition.

Referring to the drawing, there is shown a preformed expansion joint comprising a resilient filler strip 2 of compressible material enclosed in a casing formed by wall members 3. The wall members 3 forming the casing are similar in structure and may consist of any suitable flexible metal. If desired, such members may be reenforced with stiffening ribs or other forms of reenforcement designed to provide rigidity and strength to the members and to aid in anchoring or bonding the joint between adjacent sections of paving. The wall members 3 terminate in upper and lower inwardly extending flanges 4 positioned in spaced relationship to similar 'flanges of the opposite wall member and to the posed of granulated cork agglomerated with a thermo-setting binder and formed in any suitable shape. A strip so formed is compressible to substantially fifty percent of its original thickness and is capable of rapid recovery after the compressing force is removed. If desired, the strip 2 may be composed of any other resilient or compressible material possessing the property of rapid and approximate return to its original thickness after deformation, such as natural cork, cork and rubber compositions, rubber or similar materials.

A composition suitable for use for the manufacture of filler strips may comprise comminuted or granulated cork'bound together by a thermosetting binder consisting of a phenolic condensation product formed by the reaction of phenol lows: Phenol, paraformaldehyde, sodium hy- H droxide as a catalyst for the condensation product, and glycerine are mixed together and heated to about 200 F. and held at such temperature until test shows that a sample of the liquid will set when held at 300 F. for three minutes. The reaction is then interrupted, and the intermediate product is mixed with the comminuted cork. The mixture is confined in an appropriate mold at a temperature of about 300 F. which com- ;pletes the reaction and causes the comminuted cork to be agglomerated by the binder, providing a cohesive mass of desired shape.

In assembling the joint, the metal wall members 3 are positioned about the strip 2 forming a casing enclosing the same. The wall members 3 are forced toward one another by any suitable means of pressure (not shown) to compress the strip '2 to any predetermined extent, thereby aligning the openings 5 in the flanges 4. In other words, the filler is initially compressed sufflciently to compensate for contraction of adjacent paving sections with which it will be used. The casing is locked in fixed position .by placing pins 6 through the openings 5 and forcing them through the filler 2 to extend through similar openings 5 in the lower flanges 4, thereby maintaining the strip 2 in compressed condition in the casing.

In Figure 3, I have shown the expansion joint in use filling the space between adjacent sections 1 and 8 of concrete paving positioned in spaced relationship to one another on a road bed sections slightly greater in width than the Width of the expansion joint to be positioned therein.

When the sections have set, the joint is positioned in such space and the pin 6 removed, permitting the filler 2 to recover as much of its original thickness as is permitted by the sec- .tions and completely filling the space therebetween. Preferably, such sections are cast slight- .ly greater in depth than the joint in order to provide space for a plastic or semi-plastic material In which may be placed over the joint to conceal the joint and prevent distortion or breakage of the upper flanges 4 by vehicular traflic. Such plastic or semi-plastic material may be composed of asphalt, rubber with a vermiculite filler, fibrous material with an asphaltum binder or similar materials.

If desired, the joint may be positioned on a road bed, and adjacent sections of paving cast adjacent thereto. After the sections have set, the pins 8 may be removed releasing the filler so that it is free to expand to its original thick- -ness if it were not restrained from such expanjoint may be used with any of the usual dowel .bar or load transference assemblies.

The modification shown in Figures 4 and 5 is generally similar to the above described joint. In this case, there is shown a compressible filler ll enclosed in a casing l2 formed of a single metal strip having a U-shaped form in cross section and terminating in inwardly directed flanges l3 in overlapping relationship with one another and with the filler strip I I. Preferably, the bottom of the casing is curved or bent inwardly in order that compressing forces may force it inwardly and upwardly toward the filler to avoid distorting or crumpling it when the filler strip is compressed. The filler strip II is compressed by forcing the walls of the casing toward one another, and held in compressed form by locking the walls in fixed position by means of pins l4 extending through openings (not shown) in the flanges l3 into the filler strip ll. Such joint may be positioned in paving structures in the manner illustrated in Figure 3.

It will be understood my invention may be embodied in other forms if desired. For example, the wall members may terminate in inwardly directed tabs having openings therein for the reception of pins rather than in the form of flanges as shown. If desired, means other than pins may be used to lock the casing to retain the filler in compressed form. For example, opposite flanges may be formed with interfitting notches, teeth, indentations or crimped portions of predetermined size so arranged as to engage and interlock with one another when the filler is held in compressed form.

The many advantages of the described joint are readily apparent. The device is economically manufactured and used, and may be readily,

'quickly and easily placed in a paving structure by relatively unskilled labor. It compensates adequately for expansion and contraction of adjacent sections of concrete and does not deteriorate under the impact of vehicular traffic or extended exposure to severe weather conditions.

While I have described and illustrated a preferred embodiment of my invention, it will be understood the invention is not so limited since it may be otherwise embodied within the scope of the following claims.

I claim:

1. A preformed expansion joint adapted for use in sectional concrete paving or similar structures comprising a resilient filler strip, a casing U-shaped in cross section enclosing said strip and holding it under compression, said casing terminating in inwardly directed flanges positioned in overlapping relationship to one another and to said strip, and releasable means securing said flanges in fixed position thereby maintaining said strip in compressed condition.

2. A preformed expansion joint adapted for use in sectional concrete paving or similar structures comprising a. resilient filler strip, a casing U-shaped in cross section enclosing said strip and holding it under compression, said casing terminating in inwardly directed flanges positioned in overlapping relationship to one another and to said strip, said flanges having aligned openings therein, and a pin extending through said aligned openings holding said flanges in fixed position thereby maintaining said filler strip in compressed condition.

3. A preformed expansion joint adapted for use in sectional concrete paving or similar structures comprising a resilient filler strip, separate .wall members adapted to form a casingenclosing said strip and holding it under compression, each wall member terminating in inwardly extending top and bottom flanges positioned in overlapping relationship to similar flanges of the opposite wall member, said flanges having aligned openings therein, and a pin extending through the aligned openings in the top and bottom flanges holding said flanges in fixed position thereby maintaining said filler strip in compressed condition.

4. A preformed expansion joint adapted for use in sectional concrete paving or similar structures comprising a resilient filler strip, a casing U-shaped in cross section enclosing said strip and holding it under compression, the base of said casing being bent inwardly toward the filler strip, the casing at its upper end terminating in inwardly directed flanges positioned in overlapping relationship to one another and to said strip, said flanges having aligned openings therein, and a pin extending through said aligned openings holding said flanges in fixed position thereby maintaining said filler strip in compressed condition.

5. A preformed expansion joint adapted for use in sectional concrete paving or similar structures comprising a preformed resilient filler strip, separate wall members adapted to form a casing enclosing said strip and holding it under compression, each wall member terminating in inwardly extending flanges positioned in overlapping relationship with similar flanges of the opposite wall member, and temporary means engaging said flanges to secure the wall members to one another to form a casing enclosing said strip and maintaining it in compressed condition.

6. A preformed expansion joint adapted for use in sectional concrete paving or similar structures comprising a resilient filler strip of com minuted cork agglomerated with a binder, said strip being compressible to substantially fifty per cent of its original thickness and being capable of rapid recovery to its original thickness after the compressing force is removed, a casing enclosing said strip and holding it under compression, said casing comprising separate wall members, each wall member terminating in inwardly extending flanges positioned in overlapping relationship with similar flanges of the opposite wall member and with said strip, and releasable means securing the casing in fixed position thereby maintaining said strip in compressed condition.

7. A preformed expansion joint adapted for use in sectional concrete paving or similar structures comprising a resilient filler strip of comminuted cork agglomerated with a binder, said strip being compressible to substantially fifty per cent of its original thickness and. being capable of rapid. recovery to its original thickness after the compressing force is removed, a casing U- shaped in cross section enclosing said strip and holding it under compression, said casing terminating in inwardly directed flanges positioned in overlapping relationship to one another and to said strip, and releasable means securing said flanges in fixed position thereby maintaining said strip in compressed condition.

8. A preformed expansion joint adapted for use in sectional concrete paving or similar structures comprising a resilient filler strip, a casing U-shaped in cross section enclosing said strip and holding it under compression, the base of said casing being convex with respect to the filler strip, and terminating at its upper end in inwardly directed flanges positioned in overlapping relationship to one another and. to said strip, and releasable means securing said flanges in fixed position thereby maintaining said strip in compressed condition.

WILLIAM W. KINZER. 

